The digital stream playback control technology is a technology for playing back a digital stream recorded on a recording medium such as an optical disc, in accordance with a user operation. In playback apparatuses supporting the DVD-Video or BD-ROM, the user operation is received via a displayed interactive screen that is structured using graphics. The interactive screen is provided with GUI parts called buttons. The user can perform a focus move operation and then a confirmation operation onto a button, to determine a chapter to play back, or to switch audio or subtitles. Appealing to the eyes of the user, operations achieved via such an interactive screen are user friendly, and are expected to spread furthermore.
The document identified below discloses one of prior art technologies for reading a digital stream recorded on a recording medium and playing back the read digital stream.    Document 1: Japanese Patent Application Publication No. 2000-228656